Process for the preparation of monocyclic ketones and their alkyl derivatives having more than nine ring members



Patented Feb. 19, 1929.

UNITED STATES.

A 1,702,844 PATENT OFFICE.

LEOPOLD BUZICKA, OF GENEVA, SWITZERLAND, ASSIGNOR TO M. NAEF (00., 01? GENEVA, SWITZERLAND, A COMPANY OF SWITZERLAND.

'IPROCESS FOR THE PREPARATION OF MONOCYCLIC KETONES AND THEIR ALKYL DE- RIVATIVES HAVING MORE THAN NINE RING MEMBERS.

N Drawing. lAppl ieation filed November 19, 1926, Serial No. 149,536, and in Switzerland December In the prior application Serial No. 36,049 filed June 9, 1925, there is described a process of preparing monocyclic ketones having more than nine ring members, which comprises 5 heating a normal straight chain aliphatic dicarboxylic acid salt ofthe fourth group of the periodic system especially thorium and cerium, said acid having a carbon chain containing more than ten carbon atoms, the carboxylic acid groups being linked to the end carbons thereof.

It has also been discovered that in ageneral manner for the preparation of monocyclic ketones having more than nine ring members and of their alkyl derivatives, from the dicarboxylic acids having more than ten carbon atoms in a normal chain or from their alkyl derivatives, the metals and the compounds of metals belonging to the third group of the periodic system may advantageously be employed.

According to the present invention alumin- I ium which belongs to the said metals, or its compounds such as for instance aluminium oxide are employed either alone or mixed with another metal or metal compound belonging to the said third group of the periodic system.

It-is also advantageous to use a mixture of several metals of the fourth' group of the periodic system or of the rare earths, these-- mixtures being obtained artificially or otherwise.

Mixtures of the above mentioned dicarboxylic acids or their alkyl derivatives, pre- (CHDFOOO OKs-(H v Ah-QOHx-l (CHihr'COO a 90 compounds.

. Ewample 2.

a methyl 4 mam 7 1.14 dicarboxylic' pared from the pure acids or as they are obtamed in certain technical methods or from natural products give, according to the present lnvention, mixtures of the ketones, or the1r alkyl derivatives, which, in this fdrm, can also be employed in practice.

For obtaining the mentioned monocyclic ketones, it is possible to directly heat the acids or the acid anhydrides alone or in presence of metals or metal compounds at a comparatlvely high temperature, instead of first transforming the corresponding dicarboxylic acids into salts. In this case the use of metals of the third group of the periodic sys tem is also advantageous.

The ketones or their alkyl derivatives 0btamed by the described process can be used as perfumes or as primary materials for the preparation of other technically important compounds.

Example 1.

The aluminium salt of 3-methyl-tetradecane-1.14-dicarboxylic acid is heated, preferably in a vacuum, up to a temperature of 300 to 500 degrees Centigrade and the distillate obtained therefrom is worked up by fractional distillation. The fractions distilling at from 100 to 150 C. at a pressure of 0.5 mm. are then treated with semica'rbazide or other reagent usually employed for isolating the ketones.

The formation of the 13-methyl-eyclopentadecanone can be represented by the following equation:

oo+A1.0.+sco.

acid is heated up to above 300 to 500 degrees centigrade and towards the end of the reaction preferab'y in a vacuum with aluminium hydroxide in a quantity which does not suffice for completely converting the acid into the normal salt. The product obtained is treated according to the method described in Example 1.

. Example 3.

A mixture of the aluminium and cerium salts. of 4-methyl-tetradecane-1.14-dicarboxylic acid is heated and worked up as described in Example 1. The l-methyl-cyclopentadecanone obtained boils at about 125 C. (at 0.3 mm.) gives a semicarbazone melting at about 166 C. and has a smell like that of natural musk and can therefore be used as a perfume and for preparing other interesting technical compounds.

, Example .4.

4 methyl tetradecane 1,14 dicarboxylic acid is heated at about 300 to 500 C. and towards the end of the reaction preferably in a vacuum with aluminium oxide. The product obtained is Worked up as described in Example 3.

Ewample 5.

The aluminium salt of tetradecanedld-dicarboxylic acid is heated and Worked up as described in Example 1. The cyclo-pentadecanone is obtained which distills at about 120 C. (at 0.3 mm.) and melts at 63 CL Example 6.

Tetradccane-l.ld-dicarboxylic acid is heated at about 300 to 500 C. towards the end of I the reaction preferably in vacuum with alu- A ployed for isolating the ketones. ,The cyminium hydroxide. The distillateresulting therefrom 'is worked up as described in Example 5.

sam le 7.

The anhydride of tetradecane-ll l-dicarboxylic acid is heated to about 300 to 500 C. towards the end of the reaction preferably in a vacuum with aluminium hydroxide and worked up as described in Example 5.

Emample 8.

An aluminium salt of tetradecane-1.14-dicarboxylic acid is prepared by partially neutralizing this dicarboxylic acid with sodium hydroxide and precipitating With aluminium chloride. The resulting aluminium salt is decomposed by heating and worked up as described in Example 5.

Ewample 9.

- The aluminium salt of octadecane-1.18-dicarboxylic acid is heated preferably in a vacuum to about 300 to 500 C. and the resulting distillate is Worked up by fractional distillation. The fraction distilling at from 140 to 180 C. (at 0.3 mm.) is then treated with semicarbazide or other. reagent usually em- Ezrample 10.

A mixture of cyclopentadecanone and cyclohoxadecanone is obtained by working up according to the method described in example 1 a mixture of aluminium and cerium salts of tetradecane-l.l l-dicarboxylic and pentadecane-1.1fi-dicarboxylic acid.

I claim:

1. A process for the'preparation of monocyclic ketones having more than nine ring members comprising heating salts of a metal belonging to the third group of the periodic system of polymethylene dicarboxylic acids having more than ten carbon atoms in a normal chain the carboxylic acid groups being linked tothe end carbons thereof.

2. A process for the preparation of monocyclic ketones having more than nine ring members comprising heat-mg aluminium salts of polymethylene-dicarboxylic acids, having more than ten carbon atoms in a. normal chain the carboxyl'ic acid groups being linked to the end carbons thereof. 7 I

3. A process for the preparation of monocyclic ketones having more than nine ring members comprising heating a mixture of polymethylene dicarboxylic acid salts of metals belonging to the third group of the periodic system, havingmore than ten carbon atoms in a normalichain the carboxylic acid groups being linked to the end carbons thereof. 4'. A process for the preparation of monocyclic ketoneshaving more than nine ring members comprisingheating a'mixture of aluminium salts and thorium salts of polymethylene dicarboxylic. acidshaving more than ten carbon atoms in a normal chain the carboxylic acid groups being linked to the end carbons thereof.

In testimony whereof I afiix my signature.

LEOPOLD RUZIOKA. 

